Please Help!

Hi all, so I stopped BC in January (BC I took for a year and some months). Mid January I had a light period, and by the last days of January I had a normal period. In the month of January I did have unprotected sex.. This month I've been feeling odd. First days I had cramping and headaches, which subsided by mid month. But bloating took place up to this day. On Monday and Tuesday I had pink to brownish spotting. My expected period is due next week on February 27th. All of this week I've been feeling tired. I've even taken naps which is not normal for me. And just recently back to having mild cramps and headaches. I've also had some hip and back pinch-like thing going on. Sorry, I don't know how else to explain it.. My sister and co-worker say I might be pregnant, but I doubt it since last time I had sex was on January 20th. So I'm really confused. Anyone had this happened or is it really a sign that I should test soon? Thank you!